1. Field of the Invention
The present invention relates to lubrication and, more particularly, to a lubrication system suited for independently lubricating the engine components and the accessory components of a gas turbine engine.
2. Description of the Prior Art
It is known to independently feed lubricant to the accessory components and the engine components of a gas turbine engine. This is typically achieved by providing two separate oil tanks, one for accessory lubrication and one for engine lubrication. Each tank is connected to a distinct lubricant re-circulating circuit for respectively feeding oil to the engine components and the accessory components. Each tank must have its own filler port and its own oil level indicator. This tank duplication represents additional work for the technician, which must fill two tanks and thereafter monitor two different levels of oil. The use of two tanks also contributes to increase the overall weight of the gas turbine engine lubricating system and requires additional space, which is not suitable due to size constraints on a gas turbine engine.
It is therefore an aim of the present invention to provide a new supply tank, which facilitates maintenance of a dual independent lubrication system.
It is a further aim of the present invention to minimize the weight and part numbers of a lubrication system having two independent lubricant circulating circuits.
It is a further aim of the present invention to provide a gas turbine engine lubrication system comprising a tank having two chambers for lubricating engine and accessory components separately.
Therefore, in accordance with the present invention, there is provided a lubrication system for lubricating gas turbine engine components and accessory components separately, comprising first and second lubricant circulating circuits for separately feeding lubricant to the engine components and the accessory components, a supply tank with first and second separate chambers respectively connected in fluid flow communication with said first and second lubricant circulating circuits, a filler port for allowing said first chamber to be filled with lubricant, and a filling and level maintaining circuit connected to said first lubricant circulating circuit for directing a portion of the lubricant fluid pumped from said first chamber into said second chamber, thereby allowing said second chamber to be initially filled and the level of lubricant contained therein subsequently maintained at a predetermined level.
In accordance with a further general aspect of the present invention, there is provided a lubrication system for separately supplying lubricant to first and second set of components, comprising first and second lubricant circulating circuits for separately feeding lubricant to the first and second sets of components, said first and second lubricant circulating circuit being fed by a common supply tank having first and second separate chambers respectively connected in fluid flow communication with said first and second lubricant circulating circuits, a filler port defined in said supply tank for allowing said first chamber to be filled with lubricant, a pump for withdrawing lubricant from said first chamber, wherein a first portion of the lubricant pumped from said first chamber is directed to the first set of components via said first lubricant circulating circuit before being returned back to said first chamber, whereas a second portion of the lubricant fluid pumped from the first chamber is directed into said second chamber through a filling and level maintaining circuit connected to receive a flow of lubricant from said first chamber to initially permit filling of said second chamber and to subsequently maintain a predetermined volume of lubricant in said second chamber.
In accordance with a further general aspect of the present invention, there is provided a dual supply tank for independently supplying lubricant to a gas turbine engine lubricating circuit and an accessory lubricating circuit. The tank comprises first and second separate chambers adapted to separately feed the gas turbine engine lubricating circuit and the accessory lubricating circuit, a single filler port for filling said first chamber, a nozzle for directing a flow of lubricant from said first chamber to a scupper, said scupper being connected in flow communication with said second chamber for allowing filling of said second chamber up to a predetermined level and thereafter redirect the excess lubricant flowing out of the nozzle away from said second chamber.